ampeg_attack
EG attack time.
Examples
ampeg_attack=1.2
fileg_attack=0.1
Practical Considerations
These are very frequently used, especially with amplifier envelopes.
ampeg_attack is the standard "A" in the basic ADSR volume envelope.
fileg_attack is key to 303-style basses.
In ARIA, the SFZ1 envelopes have linear attack (for pitcheg and fileg,
probably linear in cents, which won't translate into linear in Hertz).
Decay and release stages have a curve which is faster than linear, and it
seems to match "well enough" with a multiplicatively decreasing curve.
The step size should be close to
\(\mu = \exp \left( - \frac{8.0}{t \times s} \right)\)
where \(t\) is the decay duration in seconds, and \(s\) is the sample rate in Hertz.
The envelope \(x_{n+1}\) at index \(n+1\) is thus computed as
\(x_{n+1} = \mu \times x_{n}\).
Here is a screenshot of a file output using Sforzando, showing the ampeg_envelope shape and its stages.
| Name | Version | Type | Default | Range | Unit |
|---|---|---|---|---|---|
| ampeg_attack | SFZ v1 | float | 0 | 0 to 100 | seconds |
| Modulations | |||||
| ampeg_attackccN | float | 0 | -100 to 100 | seconds | |
| ampeg_attack_curveccN | ARIA | integer | 0 | 0 to 255 | N/A |
| ampeg_vel2attack | float | 0 | -100 to 100 | seconds | |
Category: Modulation, Envelope Generators